From 3ad1d32744ef4f0eb92b1989ef7b488cb7dc740d Mon Sep 17 00:00:00 2001 From: Sergei Shtylyov Date: Thu, 3 May 2018 22:36:37 +0300 Subject: PCI: rcar: Poll PHYRDY in rcar_pcie_hw_init() In all the R-Car gen1/2/3 manuals, we are instructed to poll PCIEPHYSR for PHYRDY=1 at an early stage of the PCIEC initialization -- while the driver only does this on R-Car H1 (polling a PHY specific register). Add the PHYRDY polling to rcar_pcie_hw_init(). Note that without the special PHY driver on the R-Car V3H (R8A77980) the PCIEC initialization just freezes the kernel -- adding the PHYRDY polling allows the init code to exit gracefully on timeout (PHY starts powered down after reset on this SoC). Signed-off-by: Sergei Shtylyov Signed-off-by: Lorenzo Pieralisi Reviewed-by: Rob Herring Reviewed-by: Simon Horman --- drivers/pci/host/pcie-rcar.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'drivers/pci/host') diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c index e403c5206b24..fa084477a3cd 100644 --- a/drivers/pci/host/pcie-rcar.c +++ b/drivers/pci/host/pcie-rcar.c @@ -37,6 +37,8 @@ #define PCIECDR 0x000020 #define PCIEMSR 0x000028 #define PCIEINTXR 0x000400 +#define PCIEPHYSR 0x0007f0 +#define PHYRDY BIT(0) #define PCIEMSITXR 0x000840 /* Transfer control */ @@ -527,6 +529,20 @@ static void phy_write_reg(struct rcar_pcie *pcie, phy_wait_for_ack(pcie); } +static int rcar_pcie_wait_for_phyrdy(struct rcar_pcie *pcie) +{ + unsigned int timeout = 10; + + while (timeout--) { + if (rcar_pci_read_reg(pcie, PCIEPHYSR) & PHYRDY) + return 0; + + msleep(5); + } + + return -ETIMEDOUT; +} + static int rcar_pcie_wait_for_dl(struct rcar_pcie *pcie) { unsigned int timeout = 10; @@ -551,6 +567,10 @@ static int rcar_pcie_hw_init(struct rcar_pcie *pcie) /* Set mode */ rcar_pci_write_reg(pcie, 1, PCIEMSR); + err = rcar_pcie_wait_for_phyrdy(pcie); + if (err) + return err; + /* * Initial header for port config space is type 1, set the device * class to match. Hardware takes care of propagating the IDSETR -- cgit v1.2.3